Question

A tube 1.20 m long is closed at one end. A stretched wire is placed near the open end. The wire is 0.330 m long and has a mass of 9.60 g. It is fixed at both ends and oscillates in its funda- mental mode. By resonance, it sets the air column in the tube into oscillation at that column’s fundamental frequency. Find (a) that frequency and (b) the tension in the wire.

Answer 1

The frequency is

$$f=\dfrac{c}{4·L_p}=\dfrac{343}{4·1.2}=71.5\text{ Hz}.$$

The tension is

$$T=4mL_wf^2=64.8\text{ N}.$$